Cellulosic Grewia Optiva fibres: Towards chemistry, surface engineering and sustainable materials

Natural fibres are abundantly available in nature and their properties largely depends on their physical features and chemical composition. The Himalayan Grewia Optiva fibre is one such natural fibre that is extracted by processing "shoots of Grewia optiva tree" (Grewia oppositifolia). The composite materials manufactured by utilizing natural fibres possess remarkable mechanical, thermal, and physico-chemical properties attributing to their chemical composition and structural dimensions. However, further "upgrade in the aforementioned properties of natural fibre-based bio-composites can be accomplished if the interfacial attachment between the fibre and matrix is enhanced", which can be done by surface functionalization of the fibres. In this review article, the impact of various surface functionalization strategies on mechanical, thermal, chemical resistance, water absorption and, moisture absorption properties of Grewia optiva fibre have been discussed to set up surface functionalization strategies as a viable process in consolidating valuable Grewia optiva fibre for industrial applications. The surface-functionalized Grewia optiva fibres reinforced composites, thus, prompts the development of Grewia optiva fibre as a reliable and suitable sustainable material for manufacturing of different industrial components that will help t in developing green materials for the feasible future.